B01D 2275/305
Porosity decreasing in flow direction
B01D2275/305 (Porosity decreasing in flow direction) appears on 39 US grants and 40 published applications in this corpus.
Search patents in B01D- Granted patents
- 39
- Published applications
- 40
- Assignees
- 36
- Inventors
- 108
- Latest grant
- 27 Jan 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1982 | 1 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 0 | 0 |
| 1986 | 1 | 0 |
| 1987 | 2 | 0 |
| 1988 | 0 | 0 |
| 1989 | 1 | 0 |
| 1990 | 0 | 0 |
| 1991 | 0 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 0 | 0 |
| 1995 | 1 | 0 |
| 1996 | 0 | 0 |
| 1997 | 2 | 0 |
| 1998 | 1 | 0 |
| 1999 | 0 | 0 |
| 2000 | 1 | 0 |
| 2001 | 1 | 1 |
| 2002 | 3 | 1 |
| 2003 | 2 | 4 |
| 2004 | 3 | 4 |
| 2005 | 2 | 2 |
| 2006 | 2 | 5 |
| 2007 | 0 | 2 |
| 2008 | 0 | 1 |
| 2009 | 0 | 4 |
| 2010 | 1 | 2 |
| 2011 | 1 | 0 |
| 2012 | 3 | 4 |
| 2013 | 3 | 0 |
| 2014 | 1 | 0 |
| 2015 | 0 | 2 |
| 2016 | 0 | 1 |
| 2017 | 1 | 1 |
| 2018 | 1 | 0 |
| 2019 | 2 | 1 |
| 2020 | 1 | 0 |
| 2021 | 0 | 2 |
| 2022 | 0 | 1 |
| 2023 | 0 | 2 |
| 2024 | 0 | 0 |
| 2025 | 1 | 0 |
| 2026 | 1 | 0 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Filter holding device, developing device, process cartridge, and image forming apparatus27 Jan 2026US 12,533,617 B2Ricoh Company, Ltd.
- Filter holding device, developing device, process cartridge, and image forming apparatus30 Dec 2025US 12,508,527 B2Ricoh Company, Ltd.
- Slip ring system and electrical machine having a slip ring system of this kind17 Nov 2020US 10,840,774 B2Bayerische Motoren Werke Aktiengesellschaft
- Method of manufacturing fiberglass filtration media16 Jul 2019US 10,351,462 B1Superior Fibers, LLC
- Filtering medium for air filter, filter pack, air filter unit, and method for producing filtering medium for air filter23 Apr 2019US 10,265,654 B2Daikin Industries, Ltd.
- Air filter medium, filter pleat pack, and air filter unit23 Nov 2023US 2023/0372858 A1Nitto Denko Corporation
- Filter holding device, developing device, process cartridge, and image forming apparatus19 Oct 2023US 2023/0330582 A1Ricoh Company, Ltd.
- Filter holding device, developing device, process cartridge, and image forming apparatus15 Dec 2022US 2022/0395771 A1Ricoh Company, Ltd.
- Filter assembly22 Apr 2021US 2021/0113951 A1Arun Co., Ltd.
- Filter media having an optimized gradient8 Apr 2021US 2021/0101100 A1Hollingsworth & Vose Company
Most cited
By later US patents
- Multistage micronic in-line after-air filter86US 4,704,143 A1987
- Particulate contamination control method and filtration device77US 4,604,111 A1986
- Molded panel filter76US 4,701,197 AAllied Corporation · 1987
- System and method for controlling emissions created by spraying liquids from moving vehicles53US 5,470,176 AManhole Adjusting Contractors Inc. · 1995
- Composite filter and method of making the same42US 7,094,270 B2Airflo Europe N.V. · 2006